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  <meta charset="UTF-8">
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  <title>Document</title>
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<body>
  <script>
    function array(num) {
      let arr = num - 105
      if (arr < 30) {
        return '偏瘦'
      }
      else if (arr > 30) {
        return '偏重'
      }
    }
    console.log(array(165));
  </script>
</body>

</html>